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In the field of minimally invasive surgery, the design of puncture instruments directly determines surgical efficiency and safety. As an innovative puncture device, the disposable dual-end trocar breaks the functional limitations of conventional single-ended trocars with its unique dual-end structure, emerging as a vital option for laparoscopic, thoracoscopic and other surgeries. This paper deeply dissects the core technology of disposable dual-end trocars from the perspectives of design principles, key components and manufacturing procedures.

I. Definition and Value of the Dual-End Structure

A traditional trocar consists of a single sharp obturator and an outer cannula, primarily applied to establish access pathways into body cavities. By contrast, the disposable dual-end trocar is equipped with functional tips of distinct purposes at two ends. One end is a standard sharp puncture tip for initial penetration of the abdominal or thoracic wall; the other serves as a blunt dilating tip or a functional tip with side holes for subsequent instrument insertion, gas circulation or fluid drainage. This design of "one tip for puncture, the other for manipulation" eliminates frequent instrument replacement for surgeons and drastically cuts operative time.

II. Key Components and Material Selection

Per referenced documents, the major components of the disposable dual-end trocar are listed as follows:

• Dual-ended Obturator One end features a conical or triangular tip fabricated from medical-grade 304 or 316 stainless steel, with precision grinding to deliver sharp, symmetrical cutting edges. The opposite end is rounded blunt or engineered with special grooves to guide catheters or optical fibers. Some premium models integrate miniature cameras or sensors on the blunt end to enable visualized puncture.
• Outer Cannula It is commonly made of transparent medical polycarbonate or stainless steel, with a length matched to the obturator. A sealing valve is fitted at the front end to prevent gas leakage, while a threaded connector at the rear attaches to pneumoperitoneum insufflators or suction devices. The dual-end layout allows both cannula ends to function as working channels, greatly boosting operational flexibility.
• Sealing and Locking Mechanisms Composed of elastic gaskets, spring valves and latches, these parts sustain airtightness during puncture and instrument exchange. Most are manufactured from medical silicone or TPE, balancing flexibility and long-term durability.

III. Critical Steps in Manufacturing

The production of disposable dual-end trocars adheres to rigorous process flows:

• Ultra-precision Machining: CNC lathes turn and mill stainless steel blanks to shape the profile of dual-ended obturators. Geometric angles of needle tips (such as 12° bevel or 30° taper) are controlled within a tolerance of ±0.1 mm to evenly distribute puncture force.
• Surface Treatment: Obturator surfaces undergo electrolytic polishing or coating (PTFE or diamond-like carbon coatings) to reduce friction coefficients during puncture and improve corrosion resistance. Coatings typically range 2–5 μm thick and must pass adhesion tests.
• Injection Molding: Plastic parts including cannulas and handles are injection-molded with medical PC or ABS. Molds demand ultra-high precision to maintain a fitting clearance under 0.05 mm between cannula and obturator.
• Assembly and Sterilization: Assembly of dual-ended obturators and cannulas is completed in Class 10,000 or Class 100 cleanrooms, followed by ethylene oxide (EO) or gamma ray sterilization. Every batch undergoes leakage tests, puncture force measurements and visual inspections.

IV. Specialized Quality Control Requirements

The increased functional complexity of the dual-end structure imposes two extra priorities for quality inspection. First, concentricity of the dual-ended obturator must be guaranteed to align the central axes of both ends and prevent tissue laceration caused by wobble. Second, sealing components must withstand simulated instrument exchanges of no fewer than 50 cycles without failure. Full-process traceability records under the ISO 13485 quality system create complete quality files for every single device.

Conclusion

The design of disposable dual-end trocars embodies the engineering philosophy of "multi-purpose integration". Through sophisticated dual-end architecture, optimized material matching and strict manufacturing standards, it achieves a balance of high puncture efficiency and convenient manipulation. As minimally invasive surgery advances toward finer precision, this innovative instrument is poised to become standard surgical equipment.